The movie based on Gillian Flynn's novel, which features a screenplay the author wrote herself, had a big opening weekend and looks poised to win a second consecutive week at the box office. So, as always, the question for Flynn becomes "What's next?"

The immediate answer to that has been written about a lot in the past week. She's writing every episode for David Fincher's HBO series, "Utopia," effectively expanding her multimedia domination to the small screen.

But what about the format that made her a star? Flynn has previously discussed her next adult book project, which she referred to on reddit as a "big, sprawling American folkloric tale of murder." The book was rumored to have a 2015 release date, but that no longer looks like the case.

The problem is that "Utopia" and the tail end of "Gone Girl" have pulled her attention away from finishing the book.

"Oh, I wish it were done. I was kind of getting ready to settle down into it when I heard from David [about 'Utopia']," Flynn told MTV News. "I felt like I was literally at my desk, almost ready to go, when I got the word from him. 'Hey, I have this TV project that might take up the next year of your life. Are you in?' Of course the answer is 'yes.' After that, I'll probably go back into my weird underground office and my weird underground head and get going on the next novel, which will be fun too."

Despite her success with "Gone Girl," Flynn said that she has no ambitions at the moment to write an original screenplay, preferring the "decadence" of novels.

"Now I realize even how much more decadent, the idea that you don't have to think about budget. You don't have to think about plausibility, of the actual machinations of a set or anything," she said. "You don't have to think about, 'Can I go internally into this character's head?' You can wax on about Gouda cheese for 20 pages if you feel like it."